That sounds about right to me.
Obviously we use different colours, and different again for anything pre-2000(ish)
Reverse engineering someone else’s installation is always a pain.
Unless it’s an EIB style digital system, in which case it can be problematic working out the base addresses and messages, for certain technologies.
However, one “I’m very familiar with”, is probably the easiest to reverse engineer, as a full system read returns every bit of information you’ll ever need, other than physical locations if not (digitally) labelled well enough.
I read a horror story on here about a poor chap in Germany with a KNX system that he wanted to pull into openHAB2, but because he didn’t have the original configuration file, all he could do is wait for messages on the bus and try to work out what they were.